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201.
V. Ya. Molchanov V. M. Lyuty V. F. Esipov S. P. Anikin O. Yu. Makarov N. P. Solodovnikov 《Astronomy Letters》2002,28(10):713-720
We present the results of our tests of an acousto-optical imaging spectrophotometer with a CCD detector for astronomical observations. The tunable acousto-optical filter, based on a paratellurite single crystal with a 13 Å pass band operates in the wavelength range 6300–11000 Å. We obtained image spectra for the planetary nebula NGC 7027 in the Hα line and for Saturn in the methane absorption band, as well as Hα and continuum images for the nuclear region of the Seyfert galaxy NGC 1068. 相似文献
202.
Churyumov Klim I. Luk'yanyk Igor V. Berezhnoi Alexei A. Chavushyan Vahram H. Sandoval Lourdes S. Palma Alejandro A. 《Earth, Moon, and Planets》2002,90(1-4):361-368
We present a preliminary analysis of medium resolution optical spectra of comet C/2000 WM1 (LINEAR) obtained on 22 November
2001. Theemission lines of the molecules C2, C3, CN, NH2,H2O+ and presumably CO (Asundi and triplet bands) and C2
-were identified in these spectra. By analysing the brightnessdistributions of the C2, C3, CN emission lines along theslit of the spectrograph we determined some physical parameters of theseneutrals, such as their
lifetimes and expansion velocities inthe coma. The Franck–Condon factors for the CO Asundi bands and C2
- bands were calculated using a Morse potential model. 相似文献
203.
Picazzio Enos De Almeida Amaury A. Churyumov Klim I. Andrievski Sergei M. Luk'yanyk Igor V. 《Earth, Moon, and Planets》2002,90(1-4):391-400
We report on the preliminary analysis of the high-resolution spectrum of CometC/2000 WM1 (LINEAR), obtained on Dec. 1, 2001
with the Fiber fed ExtendedRange Optical Spectrograph (FEROS) installed on the 1.52-m telescope of ESO(Chile). Many emission
lines of the molecules C2, C3, CN, CH, CH+,NH2, CO, CO+, H2O+ and, presumably, C2
- were identifiedin the spectral range 400–900 nm.
Also, near-infrared photometry was performed on Dec. 2 and 3, with the infraredcamera (CamIV) attached to the 0.60-m Boller
and Chivens telescope of the Picodos Dias Observatory (LNA/MCT), Brazil. We report the preliminary and comparativeanalysis
of the I-J and J-H color indices. 相似文献
204.
给出恒星形成区GGD12-15的宽波段JHK和窄波段H2v=1-0S(1)近红外成像观测.观测图像揭示了致密的年轻红外星团和与红外源成协的红外星云,并发现了以H2发射结表征的星团外流活动.大多数红外点源在光学波段不可见;对76颗红外点源的JHK′测光结果显示,有32颗具有红外超,其中5颗表现原恒星特征,表明分子云中的恒星形成活动很活跃.以B8光谱型作为大质量星分界,由色星等图估计出大质量星所占星团比例为-10%~26%.GGD12—15星团的K′星等分布的峰值位于15.0mag,并在13.0mag-16.0mag平坦分布;[H—K′]色分布的峰值出现在-0.7mag,在此以上更红的星团成分占70%.在GGD12-15区新发现的氢分子发射结集中在星团中心领域,其空间分布明显与剧烈的恒星形成活动相关;有5个发射结位于分子外流的中心区域,暗示其激发可能与分子外流同源. 相似文献
205.
IUE observations of HD 62001 do not confirm the ultraviolet variability of 0.15 mag seen from the ANS observations. These
intriguing variations in ANS observations seem to be caused by a nearby (∼ 70 arcsec away) B star getting in and out of the
field of view of the telescope, which had a jitter of 20 arcsec. There seems to be no evidence for the presence of a hot companion,
either from the energy distribution or from UV variability. However, visual light variations are present. This, coupled with
the radial velocity variations, indicates a binary nature probably of Algol type.
Based on observations obtained with IUE satellite at the Villafranca Satellite Tracking Station of the European Space Agency. 相似文献
206.
Lederer Susan M. Campins Humberto Osip David J. Schleicher David G. 《Earth, Moon, and Planets》1997,78(1-3):131-136
We report the identification of gas jets in comet Hale-Bopp in OH, NH, CN, C2 and C3. This is the first time OH and NH jets without an obvious optical dust jet counterpart have been identified in narrowband
comet images. We also confirm the existence of CN jets as reported by Larson et al. (1997) and Mueller et al. (1998). Jet
features can be seen in the March and April 1997 datasets, approximately a month before and after perihelion. Our results
contribute to the understanding of both the chemical properties of the comet as well as the physical mechanisms necessary
to produce these features.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
207.
208.
We consider the problem of resolving the total luminescence spectra of two-component mixtures.Non-negativity of the constituent spectra is commonly used as a criterion to accomplish this resolution,but its application seldom leads to unique answers. Sometimes, the condition must be relaxed because nosolution satisfying non-negativity exists. In these cases judgments must be made concerning which partsof the spectra will be allowed to go negative and by how much. The wavelength component vectorgramn (WCV) is presented here as a tool for assisting theexperimenter in making these judgments. Even when non-negative resolutions exist, it may happen thatresolutions with slight negative elements will more closely match the spectra of the pure constituents.The WCV can also be used as a tool for detecting these cases. The methodology is illustrated with realdata from a two-component mixture. 相似文献
209.
Optical spectroscopic data are presented on nova LW Serpentis 1978, obtained during its decline fromV 9.0 to ≃10.2 (compared to a value of ∼ 8.0 at recorded maximum). The spectrum and its evolution compare well with a typical
nova, though the principal absorption (∼ −750 km s−l) was very weak in comparison with the diffuse-enhanced absorption (∼ −1300 km s−1). The principal absorption could be identified only in the lines of O I λλ7774, 8446, and in moderate-resolution observations
of Hα. The salient features of spectral evolution follow: The near-infrared triplet of Ca n continuously weakened. O I λ8446
was always brighter than O I λ 7774, indicating continued importance of Lyman Β fluorescence. The lines due to [O I], [N II]
and N n brightened considerably near the end of our observations (37 days from maximum). The Hα emission line was asymmetric
all through with more emission towards the red. Its emission profile showed considerable structure. Based on the individual
peaks in the Hα line profile, a kinematical model is proposed for the shell of LW Ser. The model consists of an equatorial
ring, and a polar cone on the side away from the earth. The nearer polar cone did not show significant emission of Hα during
our observations. The polar axis of the shell is inclined at a small angle (∼ 15‡) to the line of sight. 相似文献
210.
Evaluation of the results of factor analysis of sets of spectroscopically detected chromatograms is carriedout by examining the shapes of the abstract factors.This is done either by visual inspection or by analysisof the power density spectra produced from them.Owing to constraints imposed by the column functionand the spectroscopic instrument function,the information content of the chromatograms necessarilyoccurs at low spatial frequencies.As a consequence,it appears as relatively broad features in the abstractchromatograms and as a peak in the low-frequency region of the corresponding power density plot.Onthe basis of examination of the power density distribution,a well-defined distinction is made betweenprimary and secondary abstract factors.The major uncertainty encountered in determining the numberof chemical components appears to arise from effects of contaminants in reagents. 相似文献